Post-op care

Post-op care US Medical PG Question 1: A previously healthy 35-year-old woman is brought into the emergency department after being found unresponsive by her husband. Her husband finds an empty bottle of diazepam tablets in her pocket. She is stuporous. At the hospital, her blood pressure is 90/40 mm Hg, the pulse is 58/min, and the respirations are 6/min. The examination of the pupils shows normal size and reactivity to light. Deep tendon reflexes are 1+ bilaterally. Babinski sign is absent. All 4 extremities are hypotonic. The patient is intubated and taken to the critical care unit for mechanical ventilation and treatment. Regarding the prevention of pneumonia in this patient, which of the following strategies is most likely to achieve this goal?

• A. Nasogastric tube insertion
• B. Daily evaluation for ventilator weaning
• C. Subglottic drainage of secretions (Correct Answer)
• D. Oropharynx and gut antibacterial decontamination
• E. Prone positioning during mechanical ventilation

Post-op care Explanation: ***Subglottic drainage of secretions*** - This is a highly effective strategy to prevent **ventilator-associated pneumonia (VAP)** by continuously removing secretions that pool above the endotracheal tube cuff before they can be aspirated. - Endotracheal tubes with a **subglottic secretion drainage port** reduce VAP incidence by preventing microaspiration of contaminated oropharyngeal secretions into the lower respiratory tract. - This is a **specific mechanical intervention** that directly addresses one of the key pathogenic mechanisms of VAP. *Nasogastric tube insertion* - While an NG tube may be needed for feeding or gastric decompression, it does not directly prevent VAP and may **increase aspiration risk** by compromising the lower esophageal sphincter. - NG tubes can promote gastroesophageal reflux and provide a conduit for bacterial migration. *Daily evaluation for ventilator weaning* - This is also a **critical component of VAP prevention** as part of the ventilator bundle, since reducing duration of mechanical ventilation is the most effective overall strategy to prevent VAP. - However, in this question asking for a strategy to prevent pneumonia in an intubated patient, subglottic drainage is the more specific technical intervention, whereas daily weaning assessment is a broader protocol that reduces exposure time. - Both strategies are important; subglottic drainage addresses the "how" of prevention during intubation, while weaning protocols address the "duration" of risk exposure. *Oropharynx and gut antibacterial decontamination* - Selective digestive decontamination (SDD) aims to reduce bacterial colonization, but evidence for routine use is mixed and raises concerns about **antimicrobial resistance**. - Not universally recommended as a primary VAP prevention strategy in most guidelines. *Prone positioning during mechanical ventilation* - **Prone positioning** is primarily indicated for improving oxygenation in **Acute Respiratory Distress Syndrome (ARDS)**, not for VAP prevention. - While it may improve secretion drainage, it is not a standard VAP prevention measure and carries its own risks and logistical challenges.

Post-op care US Medical PG Question 2: A 37-year-old man is brought to the emergency department by ambulance after a motor vehicle accident. He suffered multiple deep lacerations and experienced significant blood loss during transport. In the emergency department, his temperature is 98.6°F (37°C), blood pressure is 102/68 mmHg, pulse is 112/min, and respirations are 22/min. His lacerations are sutured and he is given 2 liters of saline by large bore intravenous lines. Which of the following changes will occur in this patient's cardiac physiology due to this intervention?

• A. Increased cardiac output and unchanged right atrial pressure
• B. Decreased cardiac output and increased right atrial pressure
• C. Increased cardiac output and decreased right atrial pressure
• D. Increased cardiac output and increased right atrial pressure (Correct Answer)
• E. Decreased cardiac output and decreased right atrial pressure

Post-op care Explanation: ***Increased cardiac output and increased right atrial pressure*** - The patient experienced significant blood loss, leading to a **decreased preload** and subsequent **reduced cardiac output**. Volume resuscitation with saline directly increases the **intravascular volume** which bolsters **venous return** and **right atrial pressure**. - According to the **Frank-Starling mechanism**, increased right atrial pressure (a measure of preload) results in an increase in ventricular stretch and a more forceful contraction, thereby increasing **stroke volume** and **cardiac output**. *Increased cardiac output and unchanged right atrial pressure* - While fluid administration will increase **cardiac output** by improving preload, it will also directly lead to an increase in **right atrial pressure** due to the augmented venous return. - An unchanged right atrial pressure would imply no significant increase in central venous volume, which contradicts the effect of a large volume fluid resuscitation. *Decreased cardiac output and increased right atrial pressure* - This scenario is unlikely because increasing **intravascular volume** through fluid resuscitation typically aims to raise **cardiac output** by optimizing preload, not decrease it. - A decrease in cardiac output despite increased right atrial pressure could indicate **cardiac pump failure**, which is not suggested by the clinical picture of hypovolemic shock treated with fluids. *Increased cardiac output and decreased right atrial pressure* - An increase in **cardiac output** as a result of fluid resuscitation is expected, but a **decreased right atrial pressure** would contradict the mechanism of increased venous return and volume expansion. - Decreased right atrial pressure would typically indicate ongoing volume loss or inadequate fluid resuscitation to restore central venous volume. *Decreased cardiac output and decreased right atrial pressure* - Both decreasing **cardiac output** and decreasing **right atrial pressure** indicate a worsening state of **hypovolemia** or an inadequate response to fluid resuscitation. - The administration of 2 liters of saline is intended to correct the hypovolemia and improve cardiodynamics, not to worsen them.

Post-op care US Medical PG Question 3: Five minutes after arriving in the postoperative care unit following total knee replacement under general anesthesia, a 55-year-old woman is acutely short of breath. The procedure was uncomplicated. Postoperatively, prophylactic treatment with cefazolin was begun and the patient received morphine and ketorolac for pain management. She has generalized anxiety disorder. Her only other medication is escitalopram. She has smoked one pack of cigarettes daily for 25 years. Her temperature is 37°C (98.6°F), pulse is 108/min, respirations are 26/min, and blood pressure is 95/52 mm Hg. A flow-volume loop obtained via pulmonary function testing is shown. Which of the following is the most likely underlying cause of this patient's symptoms?

• A. Decreased central respiratory drive
• B. Neuromuscular blockade
• C. Bronchial hyperresponsiveness
• D. Rupture of an alveolar bleb
• E. Type I hypersensitivity reaction (Correct Answer)

Post-op care Explanation: ***Type I hypersensitivity reaction*** - The patient's acute shortness of breath, **tachycardia (pulse 108/min)**, **hypotension (95/52 mm Hg)**, and tachypnea (respirations 26/min) immediately post-surgery are highly suggestive of **anaphylaxis**, which is a severe, systemic type I hypersensitivity reaction. - The sudden onset shortly after general anesthesia and initiation of prophylactic cefazolin points to a potential allergic reaction to a medication administered during this period (e.g., **antibiotics**, **neuromuscular blockers**, anesthetics). *Decreased central respiratory drive* - This would typically lead to **bradypnea** or hypopnea rather than the tachypnea seen in this patient. - While opioids like morphine can depress respiratory drive, the patient's respiratory rate of 26/min indicates an *increased* drive. *Neuromuscular blockade* - Residual neuromuscular blockade would cause respiratory muscle weakness, leading to **shallow breathing** and potentially hypoventilation, but not typically the acute onset of shortness of breath with tachypnea and systemic hemodynamic instability observed here. - The immediate onset of symptoms also points away from persistent effects of intraoperative neuromuscular blockers, which are usually reversed before emergence. *Bronchial hyperresponsiveness* - While the patient is a smoker, which can predispose to respiratory issues, **bronchial hyperresponsiveness** (e.g., asthma exacerbation) typically presents with **wheezing**, prolonged expiration, and often hypoxemia, which are not described. - The severe hypotension and acute onset of systemic symptoms are not typical features of an isolated asthma flare-up. *Rupture of an alveolar bleb* - A ruptured bleb can cause a **pneumothorax**, leading to sudden shortness of breath and chest pain. - However, it would not typically cause **systemic hypotension** or tachycardia to this degree without other signs of tension pneumothorax (e.g., tracheal deviation, absent breath sounds).

Post-op care US Medical PG Question 4: A 25-year-old previously healthy woman is admitted to the hospital with progressively worsening shortness of breath. She reports a mild fever. Her vital signs at the admission are as follows: blood pressure 100/70 mm Hg, heart rate 111/min, respiratory rate 20/min, and temperature 38.1℃ (100.6℉); blood saturation on room air is 90%. Examination reveals a bilateral decrease of vesicular breath sounds and rales in the lower lobes. Plain chest radiograph demonstrates bilateral opacification of the lower lobes. Despite appropriate treatment, her respiratory status worsens. The patient is transferred to the intensive care unit and put on mechanical ventilation. Adjustment of which of the following ventilator settings will only affect the patient’s oxygenation?

• A. Tidal volume and respiratory rate
• B. FiO2 and PEEP (Correct Answer)
• C. Respiratory rate and PEEP
• D. Tidal volume and FiO2
• E. FiO2 and respiratory rate

Post-op care Explanation: ***FiO2 and PEEP*** - **FiO2 (fraction of inspired oxygen)** directly controls the oxygen concentration delivered to the patient, thus solely impacting **oxygenation**. - **PEEP (positive end-expiratory pressure)** prevents alveolar collapse and recruits collapsed alveoli, improving the **functional residual capacity** and thus **oxygenation** without significantly altering CO2 removal (ventilation). *Tidal volume and respiratory rate* - **Tidal volume (Vt)** directly impacts the amount of air moved with each breath, primarily affecting **ventilation** (CO2 removal). - **Respiratory rate (RR)** also directly determines the total minute ventilation, thus influencing **ventilation** more than oxygenation. *Respiratory rate and PEEP* - As mentioned, **respiratory rate** significantly affects **ventilation** by altering minute ventilation (Vt x RR). - While **PEEP** primarily affects oxygenation, the combination with respiratory rate means it's not exclusively targeting oxygenation. *Tidal volume and FiO2* - **Tidal volume** is a key determinant of **ventilation** (CO2 removal), not solely oxygenation. - **FiO2** does affect oxygenation, but its combination with tidal volume makes this option incorrect for *only* affecting oxygenation. *FiO2 and respiratory rate* - **FiO2** directly impacts **oxygenation**. - **Respiratory rate** primarily affects **ventilation** (CO2 removal), thereby influencing carbonic acid levels and pH.

Post-op care US Medical PG Question 5: A 72-year-old man presents to the emergency department after a fall. The patient was found lying down on the floor in his room in his retirement community. The patient has a past medical history of Alzheimer dementia and a prosthetic valve. His current medications include donepezil and warfarin. His temperature is 97.7°F (36.5°C), blood pressure is 85/50 mmHg, pulse is 160/min, respirations are 13/min, and oxygen saturation is 97% on room air. The patient is started on IV fluids and a type and screen is performed. Laboratory values are ordered as seen below. Hemoglobin: 13 g/dL Hematocrit: 39% Leukocyte count: 5,500 cells/mm^3 with normal differential Platelet count: 225,000/mm^3 INR: 2.5 AST: 10 U/L ALT: 12 U/L A chest radiograph and EKG are performed and are within normal limits. A full physical exam is within normal limits. The patient's vitals are repeated. His temperature is 99.5°F (37.5°C), blood pressure is 110/70 mmHg, pulse is 90/min, respirations are 10/min, and oxygen saturation is 98% on room air. Which of the following is the best next step in management?

• A. CT scan (Correct Answer)
• B. Urgent blood transfusion
• C. Fresh frozen plasma
• D. Exploratory laparoscopy
• E. Exploratory laparotomy

Post-op care Explanation: ***CT scan*** - A patient with a **prosthetic valve** on **warfarin** and a fall is at high risk for **intracranial hemorrhage**, even without focal neurological deficits. - While initial vitals improved after IV fluids, the mechanism of injury (fall) and medication profile warrant a **CT scan** of the head to rule out serious internal injury, especially given the history of dementia which might mask symptoms. *Urgent blood transfusion* - The patient's **hemoglobin (13 g/dL)** and **hematocrit (39%)** are within normal limits, indicating no acute need for blood transfusion due to hemorrhage. - Transfusions are typically reserved for patients with significant blood loss or severe symptomatic anemia. *Fresh frozen plasma* - The patient's **INR of 2.5** is within the therapeutic range for a patient with a prosthetic valve on warfarin. - There is no evidence of active bleeding or supratherapeutic anticoagulation that would necessitate the administration of **fresh frozen plasma (FFP)** to reverse anticoagulation. *Exploratory laparoscopy* - There are no clinical signs or symptoms, such as abdominal pain, distension, or evidence of intra-abdominal bleeding (e.g., declining hemoglobin, peritoneal signs), to suggest an indication for an **exploratory laparoscopy**. - The patient's physical exam was described as normal. *Exploratory laparotomy* - Similar to laparoscopy, there is no clinical evidence of acute abdominal injury or hemorrhage, which would necessitate an **exploratory laparotomy**. - This invasive procedure is reserved for cases with strong suspicion of significant intra-abdominal pathology or trauma.

Post-op care Flashcard 1 of 5

Question: Short bowel syndrome is most commonly seen in patients who have had _____

Answer: small intestine resection

Post-op care Flashcard 2 of 5

Question: What surgical procedure is associated with iron deficiency anemia?_____ *Why

Answer: Gastrectomy

Post-op care Flashcard 3 of 5

Question: Injury to the iliohypogastric nerve often presents as burning or tingling pain at the _____ radiating to the inguinal and suprapubic region

Answer: surgical incision site

Post-op care Flashcard 4 of 5

Question: Patients who have undergone _____ surgery can sometimes manifest with symptoms of hypoparathyroidism and hypocalcemia.

Answer: Thyroid

Post-op care Flashcard 5 of 5

Question: Bladder irrigation is used for patients with hematuria to prevent the formation of _____

Answer: blood clots